The islands are flat and sandy, with a few low hills. The climate is hot and humid during the summer, mild and pleasant in the winter. The largely urban population is about 62% Bahraini; the balance of the inhabitants consist of nonnationals who are mainly other Arabs or Iranians, Indians, and other Asians. Islam (75 % Shiite and 25% Sunni) is the religion of most of the population, and there are Christian and other minorities. Languages spoken other than Arabic (the official language) include English, Farsi, and Urdu. Bahrain has two universities.